Graft copolymers of mixtures of vinyl pyridine monomers and monomeric sulfonic acidsupon polyvinyllactams, acrylonitrile polymer compositions obtainable therewith, and method of preparation



y 6; s. A. MURDOCK ETAL 3,036,033

GRAFI COPOLYMERS OF MIXTURES OF VINYL PYRIDINE MONOMERS AND MONOMERICSULFONIC ACIDS UPON POLYVINYLLACTAMS, ACRYLONITRILE POLYMER COMPOSITIONSOBTAINABLE THEREWITH, AND METHOD OF PREPARATION Filed Nov. 25, 1957FILAMENTOUS ARTICLE COMPRISED-OF AN ACRYLONITRILE POLYMER HAVING A GRAFTCO- POLYMER OF A MIXTURE OF- A VINYL PYRIDINE MONOMER AND A MONOMERICORGANIC SULFONIC ACID GRAFT COPOLYMERIZED UPON A VINYL LACTAM POLYMERINCORPORATED THEREIN. I

IN VEN TORS.

STANLEY A. MURDOCK TEDDY G TRAYLOR THEODORE B. LEFFERDINK BY a HflTTOR/VEYS United States Patent GRAFT COPOLYMERSOF MIXTURES OF VINYLPYRDINE MONOMERS AND MONOMERIC SUL- FONIC ACIDS UPON :POLYVINYLLACTAMS,ACRYL'ONITRILE PQLYMER COMPOSITIONS "OBTAINABLE THEREWITH, AND METHOD OFPREPARATION Stanley -A. Murdock, Teddy G. Traylor, and Theodore B.Leiferdink, Concord, .Calif., assignors to The Dow 'ChemicalCompany,Midland, Mich., acorporation of Delaware Filed Nov. 25, 1957, Ser. No.698,770 16 'Claims. (Cl. 26045;5)

The present invention resides in the general .field of organic chemistryand contributes specifically to the polymerarhespecially with respect tocertain water-insoluble graft copolymercompositions and fiber-formingpolymer blends obtainable therewith. It is particularly concerned withgraft copolymers of mixtures of different monomers that consist of'certain'vinyl pyridine/monomers in admixture 'with certain monomericorganic sulfonic acid compounds, which monomeric admixtures are graftcopolymerized upon polyvinyllactams, to form graft copolymeric productsthat have especial utility as dye-receptive, antistatic andstabilizingadditaments'for acrylo- 'nitrile-polymer compositionswhich,advantageously, may be of the fiber-forming variety. 'The invention isalso concerned with the compositions that may be obtained by blendingthe graft copolymers with acrylonitrilepolymers, as well as with shapedarticles which have been fabricated from such compositions and which, asa consequence, have significantly enhanced properties andcharacteristics -as regards improvements in and relating to enhanceddye-receptivity, minimized inherent propensity to accumulateelectrostatic charges, natural stability to various deterioratinginfluences, including stability against polymers of the indicatedvariety; ('2) the advantageous polymer compositions,particularlyfiber-forming compositions, obtained by blending the graft-copolymerswith 'acrylonitrile polymers; (3) various shaped articles fabricate'dfrom and comprised of the graft copolymer-containing acrylonitrilepolymer compositions; and ('4) methods 'for'the preparation of theabove-indicated compositions.

It is the-main purposeand'primary design 'ofthe present invention toprovide and make available graft copolymers of admixtures of vinylpyridine monomers and certain monomeric organic sulfonic acid compoundsupon vinyl lactam polymers that are especially well suitedfor beingincorporated in acrylonitrile polymer compositions,

particularly compositions of polyac-rylonitrile, .to-serve in theindiacted'treb'le capacity .of dye-assisting'adjuvants, antistaticagents and stabilizing ingredients. It isalso a principal aim and -chiefconcernof the inventionto provide and make available acrylonitrilepolymer compositions and shaped articles therefrom that contain theaboveindicated and hereinafter more fully delineated type of graftcopolymeric additaments which compositions have, as intrinsicdistinguishingcharacteristics, excellent receptivity of andacceptability for any of a wide varietyof dyestuffs; permanently imbuedantistatic properties that are unusually .good tor and not commonlyencountered in polymeric materials of the synthetic, essentiallyhydrophobic varieties of such substances; and efficacious naturalstability to heatand light, as Well as to certain chemical conditions,such .as alkaline environments.

'Ihe graft copolymers of thepresent -invention-wh1ch have the indicatedcapacity and utility as additaments for acrylonitrile "polymercompositions are comprised of a "having a Fikentscher K-valueof about52.

polyvinyllactam trunk or base upon which there is graftcopolymerized-a-mixture of monomers consisting of vinyl pyridinemonomers in combination or admixture with certain monomeric, vinyl orothervalkenyl groupecontaining organic sulfonicacids or derivativesthereof.

The polymer blend compositions of the present invention which fulfillthe above-indicated ends and :offer corollary advantages andbenefit-s,.particularly.as.fiber=forming compositions as willhereinafterbemanifest, are, ines- "sence,-,comprised of an intimate andpractically inseparable blend or alloy constitution of (A) an.acrylonitrile polymerthat containszin the polymer molecule .atleastabout '80 percent by weight of polymerized acrylonitrile which,preferably, is ofthe*fiber-formingyariety and,'most advantageously,.ispolyacrylonitrile and (B) a minor sproportion-of theabove-indicatedvariety ofbeneficial graft copolymeric. additament that functions in thedesired manner.

The methods of the invention by whichnthe herein contemplatedadvantageous compositions -may be ,made in- ..volve preparation of:thegraft copolymer, as well as incorporation of-a minor proportion ofthe graft copolymer product as a beneficialadditament in and withtheacrylonitrile polymer base by any of several beneficial techniques,hereinafter more thoroughly defined, adapted to suitably accomplishthedesired result.

Wi-thout being limited to or by the specific embodiments and modesof'operation set -forth,-the invention is illustrated in and bythefol-lowing didactic'examples wherein, unless otherwise indicated,.all parts and percentages are to be taken on a .weight basis.

EXAMPLE A Into a SOliter flask that was equipped Withan efficient.agitator,.a nitrogenspargeranda total refluxcondenser there was chargedabout 2.2.2-'kilograms of a 47.3.6-percent aqueous solution ofpoly-N-vinyl-2-pyrrolidone (PVP) About 7. kilograms .of Water-and 15ml.ofconcentrated (38 percent) hydrochloric acid was added to the ,PVPsolution.

I he resulting acidified aqueous-solution was brought to the boil andnitrogen was then sparge'd into the reaction :mass inthereactor. Thenitrogen sparging was continued through the ensuing reaction. Over a 2hour period there was continuously fed into the stirred reaction massabout 736 ml. of 0.612. percent aqueous hydrogen peroxide solution .and7.264 liters of an aqueous monomer fcedcon- .taining a mixture ofmonomers consisting of about 717 tgramsof 41.6 percent active sodiumstyrene sulfonate and .161 grams of 94.4 percentactive 2-vinyl pyridine..After the entire quantities of the monomer andca-talyst'soluvtions'hadbeen. chargedtto the reactor, the heating vwas'continned. and thetemperature of the reaction mass .wasmain- .tained at the boil for of anhour. At thispoint, an

additionalone ml. quantity of 30 percent aqueous hydrogen peroxide wasadded and the mixture maintained at the boilffor anaddi-tional hour. Thereaction was then terminated and the graftcopolymer product was removedfrom vthereactoras a stable white aqueous dispersionof .thewater-insoluble additament in water. The aqueous dispersion containedabout 9.5 percent of water-insoluble polymer solids. '-Uponanalysis, itwas foun'd'that about 93' percent of :the mixture of monomers had been:converted to a graft copolymer'product with the PVP and that. the graftcopolymer productcontained about 10 percent of graftcopolymerized.2g-vinyl pyridine ,unitsgabout 21.9 .percent.of--polymerizedsodiumstyrene .sulfonatei-llnits;

:and :.about 71;perce.nt 10f the'PVP substrate.

Polyacrylonitrile fiberscontaining about 10 percent of :theabovecopolymer product were-prepared bydmpreg- .nating :filarnentarystructures that .were in aquagel condition (after having beensalt-spun).in and with. aqueous dispersions of the copolymer that, inthree sequential stages, contained about 1.5, 0.5 and 0.1 percent of thegraft copolymer solids, respectively. The polyacrylonitrile aqu'agelfiber that was employed had been obtained by extruding a spinningsolution of fibers-forming polyacrylonitrile comprised of about parts ofthe polymer dissolved in 90 parts of a 60 percent aqueous solution ofzinc chloride through a spinnerette having 750 individual 6 mil diameterorifices into an aqueous coagulating bath that contained about 43percent of dissolved zinc chloride to form a multiple filament tow.After being spun, the tow bundle of coagulated polyacrylonitrile aquagelfiber was washed substantially free from salt upon being withdrawn fromthe coagulating bath and then wet-stretched in the sequentialimpregnating baths at the boil for orientation with simultaneousimpregnation. The fiber was thus stretched to a total stretched lengththat was about thirteen times its original extruded length. The

aquagel fiber, which contained about two parts of water to each part ofpolymer therein, was also simultaneously impregnated with the graftcopolymer to the indicated extent during the stretching.

Following the impregnation, the aquagel fiber was ir- "reversibly driedat 150 C, to destroy the water-hydrated structure and convert it to afinished fiber form. The finally obtained 3 denier fiber product had atenacity of about 4.0 grams per denier, an elongation of about 29percent, a dry yield strength of about 1.0 gram per denier, and a wetyield strength of about 0.9 gram per denier. The graftcopolymer-containing acrylonitrile polymer fiber product was found tohave excellent natural stability to heat and light as well as againstbecoming degraded under the influence of aqueous alkaline media at pHlevels as high as 10. It was found to be nearly free of propensity toaccumulate charges of static electricity upon handling.

It addition, the graft copolymer-containing sample had good color andhand and was dyeable with all classes of dyestuffs as applied undernormal dyeing conditions. The fiber product dyed well to deep and levelshades of coloration with Calcodur Pink ZBL, a direct type of. dyestufl(Colour Index Direct Red 75, formerly Colour Index 353) and SevronBrilliant Red 46, a basic dye formerly known'as Basic Red 46 (ColourIndex Basic Red 14).

The dyeing with Calcodur Pink 2BL was performed at the 4 percent levelaccording to conventional procedure in which the fiber sample wasmaintained for about one hour at the boil in the dye bath whichcontained the dye- 4 percent Calcodur Pink ZBL reflectance value of theco polymer-containing fiber product was about 20.

The antistatic properties of the copolymencontaining fiber were thendetermined by measuring the electrical conductance of the fiber productat various humidities. As is also appreciated by those who are skilledin the art, the basis for such a test is that all fibers have a tendencyto generate static electricity upon being handled. Only those that arepossessed of sufiicient electrical conductance to dissipate the chargeas quickly as it forms are not hampered by the bothersome effect ofstatic electricity. Thus, a measure of the electrical conductance of afiber is a good indication of its ability to dissipate staticelectricity. The conductivities of the various fiber samples tested werefound by determining their electrical resistances. Resistance, ofcourse, is the reciprocal quantity of conductivity. In order to permitvarious fiber samples to be compared on a common basis, theconductivities of the samples tested were actually measured as volumeresistivities according to the following formula:

Volume Resistivity (Resistance) (Gross-Sectional Area) Path LengthBetween Electrodes to Which Sample Being Tested is Attached The units ofvolume resistivity are ohm-cmF/cm.

Prior to being tested, the graft copolymer-containing polyacrylonitrilefiber prepared in the indicated manner was vat dyed in the conventionalmanner with Cibanone Green BF Dbl. Paste (Colour Index Vat Green No. 1).A portion of the vat dyed sample was then subjected to five (5)consecutive No. 3-A accelerated wash tests in accordance with theAmerican Association of Textile Chemists and Colon'sts (AATCC) Manual.The actual resistivities of the merely vat dyed sample as well as thatof. the sample that had been both vat dyed and scoured were thendetermined (after the samples being tested were conditioned forseventy-two hours at the particular temperature and relative humidityconditions involved in each I containing fiber but without having thepolymeric additawave length of about 520 millimicrons from a standardsource that was. reflected from the dyed sample. A

numerical valueon an arbitrarily designated scale from zero to onehundred was thereby obtained. This value represented the relativecomparison of the amount of' light that was reflectedfrom a standardwhite tile reflector that had -a reflectance value of 316 byextrapolation from the 0-100 scale. Lower reflectance values are anskilled in the art to be representative of a degree of dyerece ptivitythat readily meets or exceeds the most rigorous practical requirementsand is ordinarily assured of receiving general commercial acceptance andapproval. The

ment incorporated therein) were also tested in the indicated manneralong with the graft copolymer-containing fiber in accordance with thepresent invention.

The results are set forth in the following tabulation which indicatesthe volume resistivities obtained at various relative humidities (RH) at23 C. of each of the samples tested;

Table 1 VOLUME RESISTIVITIES OF VARIOUS FIBER SAMPLES COMPARED TOPOLYACRYLONITRILE FIBERS IMPREG- NATED WITH GRAFT COPOLYIVIER OF 2-VINYLPYRI- DINE AND SODIUM STYRENE SULFONATE ON PVP Volume Resistivityohm-omfi/cm.

, As is apparent in the foregoing, the graft copolymer-containingsample,even after being severely scoured, had electrical conductanceproperties much superior to ordinary polyacrylonitrile and only slightlypoorer than cotton. At the same time, the physical properties of thecothe following reaction mass was prepared and polymerized withefiicient agitation at 60 C. for 16 hours:

44.5 percent active sodium styrene sulfonate grams 87:5 94.4 percentactive 2-vinyl pyridine do 20 45-percent active PVP (Fikentscher K-value52) grams 222 30 percent aqueous hydrogen peroxide ml '115 Water ml1,000

The reaction mass prior to thepolymerization was acidified to aboutpH 3with concentrated hydrochloric acid and the graft copolymerization wasconducted with the reaction'mass out of contact with air. The product,after polymerization, was obtained as a milky white suspensioncontaining about 11.5 percent of dispersed solids of a Water-insolublegraft copolymer product which, upon analysis, was foundto contain about.24 percent of polymerized sodium styrene sulfonate units; about 11percent of polmerized 2-vinyl pyridine units; and about 65 percent ofPVP. impregnation of the copolymer product into acrylonitrile polymerfibers in the manner set forth in the first example provided excellentresults commensurate with those demonstrated with respect to theimprovement in dye-receptivity of the fiber, reduction of its staticcharacteristics and enhancement of itsstability to heat and light.

Excellent results may also be obtainedwhen the foregoing is repeated toprepare graft copolymer additives from poly-N-vinylcaprolactarn,poly-N-vinyl-S-methyl-Z- 3" pyrrolidone, poly-N-vinylpiperidone andother vinyl lactam polymers using the same or any other of the monomeric components indicated as being useful in the practice of theinvention. Results similar to those set forth in the foregoing canlikewise be obtained when the graft copolymer additarnents areincorporated inpolyacrylonitrile and other acrylonitrile polymer fibersto provide articlesin accordance with the present invention by blendingthe graft copolymer and the fiber-containing acrylonitrile polymer in aspinning composition or dropprior to its extrusion into filamentaryproducts by either wet spinning or dry spinning techniques. In suchinstances, incidentally, it may be desirable (in order to'secure optimumbenefit in the practice of the invention), toemploy relatively largerquantitiesof the graftcopolymeric additament that when surfaceimpregnation is performed so that the presence of effective quantitiesof the additament at or near the peripheral portion of the article isassured. The vinyl pyridine monomers that are employed in the practiceof the present invention for the preparation of the graft copolymerproducts may be any of those of the general formula:

(CH=CH )-radical or groupand the remainder arerindependently selectedfrom the group consisting of "hydrotgenor'alkyl radicalscontaining fromltoabout 3 carbon atoms. Besides 2-vinyl pyridine,2-vinyl-4-methylpyridine and 2-vinyl-4-ethyl pyridine maybe-employed=with particular benefit in'the'practice of the .presentinvent-ion.

The sulfonic acid and derivative monomers'thateare employed for thepreparation of the graft copolymer products in cornbinationwith thevinyl pyridine monomers are monomeric, vinyl or other alkenylgroup-containing, organic sulfonic acids or derivatives thereof thatarei6 selected from the group of such compounds (including mixturesthereof) consistingof those representedby the formulae:

OHFC (CH1) -SO X Rm rr 1O (aromatic organic sulfonimacid. compounds) 0Hz 0 H-( 011;) 1-8 0 3X (III) (alkenyi organic sulfonic acid compounds)CH1=CC O O-(CHz) n-+sO3X (sulfoalkylacrylate compounds)CHpO-C'ONH-(OEzh-SOzX i v (acryloyl taurlne homolog compounds) allwherein X is *hydrogen, .an aliphatic "hydrocarbon radicalcontainingfrom.1.to 4 carbon atoms or an alkali metal ion (including sodium,potassium and lithium);

Y is hydrogen, chlorine or bromine; R is methyl or ethyl; Z is hydrogenor methyl; m has a numerical valueiin Whole number increments from'O to2;'n has a numerical value of 1 or 2; p is 0 or 1; and'ris l'to 4.

Besides those specifically illustrated "herein, other organic sulfonicacids may alsobe utilized forthe'preparation of the water-insoluble'COPOIYIIICIS of the present invention such, by'way of illustration, asthose which are set forth in the disclosure of United StatesLetters'Patent No. 2,527,300. ,In addition to the graft copolymersspecifically described in the .foregoing examples, other additamentsthat may advantageously be employed in the practice of the presentinvention include graft copolymers of (a) various vinyl pyridinemonomers, particularly 2-vinyl-pyridine and 2-vinyl-4-methyl-pyridine inadmixture with such organic sulfonic acids as 2-propenesulfonic acid;sodium para-vinylbenzene sulfonate; v2- and/or 3-sulfopropyl acrylate;a-sulfoacrylic acid; sodium vinyl toluene sulfonate; potassiumortho-chlorostyrene sulfonate; 2-hydroXy-3asulfopropyl acrylate, sodiumsalt; s0- dium 3-allyloxyl-2 hydroxyp-ropane sulfonate; 4-.sulfophenylacrylate, sodium salt; 'N-allyl imino di-(Z-ethane sulfonic acid);and1the like, upon a '(b) vinyl lactam --polymer, including .inparticular poly-N-vinyl 2-pyrrol- .idone (PVP) and polyN-vinylcaprolactam.

Still'othen'organic sulfonic acids thatmay 'beemployed are asset fort-hin'the following representative (but' by 'no :means exhaustive) listing,wherein they are grouped according to' the: above desi nated types:

Aromatic Alkenyl Group Containing Sulfoni'c Acid Compounds ,(For'mz'lla'Il 3-vinyl toluene 6-sulfonic acid, sodium salt 2-ethyl-4-vinyl-benzenesulfonic acid 2,3-dichloro-4-viny1 benzene sulfonic acid2,3,5-tribromo-4-vinyl benzene sulfonic acid2-chloro-3-vinyl-toluene-6-sulfonic acid 2,3-diethyl-4-vinyl-benzylsulfonate, sodium salt Alkenyl Sulfom'c Acid Com-pounds (Formula Ill)ethylene sulfonic acid sodium ethylene sulfonate potassium ethylenesulfonate methyl ethylene sulfonate isopropyl ethylene sulfonatel-propene 3-sulfonic acid l-propene l-sulfonic acid, sodium saltl-propene 2-sulfonic acid, ethyl ester l-butylene 4-sulfonic acid,n-butyl ester l-butylene 3-sulfonic acid tertiary butylene sulfonic acidSulfoalkylacrylate Compounds (Formula IV) sulfomethylacrylate 2sulfoethylacrylate sulfomethylmethacrylate, sodium saltZsulfoethylmethacrylate, methyl ester Z-suIfoethyImethacrylate,potassium salt Acryloyl Taurine and Homologous Compounds (Formula V)N-acryloyl taurine N-acryloyl taun'ne, sodium salt N-methacryloyltaurine, methyl ester N-methacryloyl taurine, potassium salt N-acryloyltaurine, ethyl ester N-acryloyl-aminomethane sulfonic acidN-methacryloyl-aminomethane sulfonic acid, sodium salt methylN-methacryloyl-aminomethane sulfonate Allyl Taurine and HomologousCompounds (Formula VI) allyl taurine allyl taun'ne, sodium salt allyltaurine, potassium salt methallyl taurine methallyl taurine, methylester methallyl taurine, isopropyl ester N-allyl-aminomethane sulfonicacid sodium N-allyl-aminomethane sulfonate lithiumN-methallyl-aminomethane sulfonate n-butyl N-allyl-aminomethanesulfonate The vinyl lactam polymers that are utilized in the preparah'onof the graft copolymeric additaments of the present invention may be anyof those (or their mixtures) which are variously characterized andgenerically known to the art as poly-N-vinyllactams' orpoly-l-vinyllactams. Such polymers as have been described or which maybe prepared from the mentioned varieties of monomers that are involvedin US. Patents Nos. 2,265,450; 2,371,804;

erally be prepared by methods of polymerization, such as those whichhave been demonstrated in the foregoing illustrative examples, thatemploy'such polymerization catalysts aspersulfates, organic andinorganic peroxide and azo type materials in quantities that areconventional for such uses. The graft 'copolyniers. may oftentimes'beprepared by polymerizing the monomeric constituent onto the vinyl Iactampolymer under the influence of high'energy irradiation such as by meansof X-tays and the like. The graft copolymers may be prepared in bothaqueous and organic solvent vehicles using temperatures for the desiredpolymerization that may vary from about room temperature to the boilingpoint of the polymerization mixture. It is ordinarily satisfactory toconduct the reaction at a temperature of about50 to 80 or 100 C.Usually, depending on the specific factors that may be involved, thegraft copolymerization may be accomplished satisfactorily within a timeperiod of about 10 to 60 hours. The compositions of the graftcopolymeric additament that is utilized can vary within rather widelimits. The content of the graft copolymerized mixed monomericconstituents may advantageously be between about 20 and 80 percent byWeight with the balance of the graft copolymer product consisting offrom 80 to 20 percent by weight of the vinyl lactam polymerupon whichthe admixed monomeric constituents are graft copolymerized. In manycases, especially to secure optimum dye-receptivity, nearly equivalentor about commensurate or equal proportions of the graft copolymerizedmixture of monomers and the vinyl lactam polymer substrate may beemployed in the preparation of the graft copolymeric additaments. Themixture of the monmers that is utilized may consist of from 10 to 90mole percent of either monomeric constituent (i.e., for example, from 10to 90 mole percent of the vinyl pyridine monomer with from 90 to 10 molepercent of the organic sulfonic acid' monomer). In many cases it is moreadvantageous for the mixture of monomers to be'comprised of from about30 to 70' mole percent of either of the monomeric constituents.

The polymerization system that is employed for the preparation of thegraft copolymers used in the present invention may consist of as much as50 percent by weight of the reactive ingredients to be polymerized inthe aqueous or other medium. The amount of 'polymerizable constituentsthat are provided in the graft copolymerizetion system may be influencedsomewhat by the manner in which it is intended to incorporate theproduct in the synthetic polymer compositions in order to provide thecompositions of the invention.

If, for example, it is intended to incorporate the graft copolymerproducts by blending into a fiber-forming composition prior to itsfabrication into shaped articles, the graftcopolymerization system may,if desired, contain about equal proportions byweight of the chargedpolymerizable constituents and the polymerization medium whichpreferably is miscible with and tolerable in the spinning solutionsolvent being used. In such cases, the graft copolymer product mayordinarily be obtained as an eaisly dispersed gel that, after beingdried and isolated from unreacted monomer, may readily be directlyincor- V porated in the fiber-forming composition.

I If the incorporation of the graft copolymeric additament in afiber-forming composition is to be achieved by impregnation therewith ofan already-formed shaped article of the composition, it may be desirableto effect the polymerization so as to directly form the polymerizationsystem as a suitable applicating emulsion or suspension of the graftcopolymeric product. For such purposes, the polymerization system may beprepared to contain as littleas 5 or 10 percent by weight of thepolymerizable monomeric and polymeric ingredients. Preferably, such agraft polymerization may be conducted under the influence of vigorousagitation to facilitate preparation of an emulsified or thoroughlydispersed product It may also be beneficialunder such circumstances toincorporate a dispersant or emulsifying agent in the polymerizationsystem to facilitate obtaining a stable and homogeneous emulsifiedproduct. Such a method for preparing the graft copolymeric additamentsthat are employed in the present invention may be especially appropriatewhen they are intended to be applied to acrylonitrile polymer fibers andthe like that are derived from aquagels in the course of theirmanufacture, such as the acrylonitrile polymer fibers that are wet spunfrom aqueous saline solutions of lthe fiber-forming polymer.

In such instances, as has been demonstrated, the emulsified,water-insoluble, graft copolymeric additaments may be impregnated intothe fiber While it is in a swollen or gel condition, as an acrylonitrilepolymer fiber in an aquagel condition, in order to obtain the desiredcopolymer-containing product.

In this connection, when it is desired to blend the "graft copolymericadditament in a synthetic polymer fiber-forming solutionprior to itsextrusion, such as an aqueous saline acrylonitrile polymer solution, thewaterinsoluble graft copolymer may be physically reduced by comminutionto a sufliciently fine state to permit its dispersion in spinnablecondition throughout the blended spinning solution in the event that itis otherwise in- :soluble in the solvent. While this may be accomplishedby diverse techniques, it is generally advantageous to comminute thegraft copolymer in the presence of the non-dissolving solvent, such asan aqueous saline poly- -acry lonit1ile solvent, to form a stablesuspension that may be more conveniently blended with the spinning:solution of the a synthetic polymer, such as an aqueous :saline'acryloninile polymer spinning'solution. Thus, if the aqueous salinepolyacrylonitrile solvent that is being employed-is an aqueous solutionof zinc chloride or its :equivalent that contains at least about 55percent and :preferably about 60 percent by weight of dissolved .zincchloride, it may be advantageous to comrninute graft-copolymericadditament while it-is in a mixture with thesaline solvent solution thatcontains between about Sand percent by weight of the copolymer.Analogous procedures may be employed when other solvents are involved.Ball or rod mills or other atitrition apparatus may be employedbeneficially for the -comminution. It is-generally beneficial under suchcircumstances to avoid the use of balls or rodsthat are -made ofmetalsince they may contaminate the product, :especially when aqueous salinesolvents are utilized. Porcelain or other ceramic parts'may usually beem- :ployed with advantage. A stable suspension of .the graftcopolymeric additament in the acrylonitri-le polymer solvent that issuitable for blending in the spinning solution of :the acrylonitrilepolymer to provide a spinnablecomposition may usually be obtained bymilling the mixture 'of graft copolymeric additament and solvent for anextended period that may exceed 100 hours. The suspensionthatis therebyobtained may then-be directly blended in the proper proportions with theacrylonitrile polymer spinning solution to provide a composition inaccordance with the present invention.

If desired, the copolymer-containiug acrylonitrile polymer compositionsmay comprise as much as 20 or more percent by weight of the graftcopolymeric additament, based on the weight of the composition. Usual-?ly, however,-suitable properties and-characteristics and betterfiber-forming properties in a given composition .may be achieved whenlesser proportions of the graft copolymeric'additament are incorporatedtherein. An .appreciable improvement in dye-receptivity, antistaticproperties and stability 'may frequently be obtained when a quantity ofthe graft copolymeric additament that is as small as 2 (and even as lowas 1 or less) percent by weight is employed. Advantageously, an amountbetween about 4 and percent by weight of the graft copolymericadditament -may"thus"be utilized in the composition. Greater advantagemay often accrue when "the amount of the garft copolymeric additamentthat is incorporated in the composition is in the neighborhood of 5-10percent by weight,'based on the weight of the composition.

-As has been indicated, the graft copolymeric additaments may beincorporated in the acrylonitr'ile polymer compositions according tovarious techniques. Thus, for example, the copolymeric additament andthe acrylonitrile polymer may be directly blended in order to'providethe composition which, incidentally, may be used for any desiredfabrication purpose in addition to fiber-forming and the like.Beneficially, the polymers maybe comminuted, either separately or incombination, before being intimately blended together by mechanical orother means. The blended polymers may be prepared into suitablefiber-formingsystems by dissolving or otherwise dispersing them inasuitableliquid medium. Or, the compositions may be provided infiber-forming system by sequentially dispersing the polymers in anydesired order in a suitable medium,as-by incorporating the copolymericadditament in a prepared acrylonitrile polymer spinning solution, dopeor 15 the like.

As is evident'frorn the'illustrative examples heretofore included, ahighly advantageous technique for providing the compositions,particularly when acrylonitrile polymer'fiber products are involved, isto apply or impregnate the copolymeric additament from an aqueousdispersion thereof to a shaped acrylonitrile polymer article that is inan aquagel condition a manner similar and analogous tothat employed forthe impregnation of vinyl lactam polymers as described in the disclosurecontained in the copending application of George W. Stanton, Theodore B.LefferdinhRichard W. Meikle'and Mary J. Charlesworth for a Method andComposition for Rendering Polyacrylonitrile Readily Dyeable havingSerial No. 333,385 which was filedon January 26, 1953, now abandoned.Thus, an acrylonitrile polymer filamentary article that has been spunfrom an aqueous saline spinning solution may be conveniently passed,after its coagulation and while it is in an aquagel condition, through awater bath containing'the dissolved graft copolymeric additament inorder to impregnate the filament with thegraft copolymer and provide acomposition and an article in accordance with the invention. Inaddition, in situ polymerization techniques may also be relied upon toprovide the copolymeric additament in the acrylonitrile polymers ineither fabricated or unfabricated form.

The compositions of the invention may advantageously be utilized in orwith fiber-forming systems of any desired type in order toprovide-fibers and the like according to procedures and techniques thatare conventionally employed for suchpurposes in the preparation offibers and such'relatedshaped articles as filaments, strands, yarns,tows, threads, cords and otherfunicular structures, ribbons, tapes,films, foils, sheets and the like which may be manufactured'fromsyntheticpolymeric materials. -It is frequently desirable to employconcentrated solutions of salts'or'mixtures of salts as the dispersingor dissolving media for suchpurposes. 'Such solutions may, as has beenindicated, contain at leastabout 55 percent by weight-based on thewcightof the solution, of zinc chloride or other known saline solvents for thepolymer. Acrylonitrile polymer fiber products that are spun fromsalinefiber-forming systemsmay, by-way of further illustration, becoagulated in more dilute saline solutions of a like or similar natureand may then-be processed after coagulation according to conventionaltechniques of washing, stretching, drying, finishing'and the like withthe'modificationof the present invention being accomplished prioror'su-bsequent to the spinning as may be desired and suitable inparticular'instances. t

The acrylonitrile polymerfiber products in accordance with the presentinvention (one of which is schematically illustrated in the sole FIGUREof the accompanying drawing) have excellent physical properties andother desirable characteristics for a textile material and have a highcapacity for and are readily and satisfactorily dyeable to deep andlevel shades of coloration with any of a wide variety-of dyestuffs. Forexample, theygmay be easily and successfully dyed according toconventional "procedures using acid, vat, acetate, .direct, basic,vnaphthol and sulfur dyes. Such dyestufis, by way of didactic1llustration, as Calcocid Alizarine Violet (Colour Index 61710, formerlyColour Index 1080), Sulfanthrene Red 3B (Colour Index Vat Violet 2),Amacel Scarlet GB (Colour Indexll110also known as Amacel Scarlet BS, and

vention include such direct cotton dyes as Chlorantine Best Green SBLL(Colour Index Direct Green 27), Chlorantine Fast Red 7B (Colour IndexDirect Red 81),

Pontamine Green GX Conc. 125 percent (Colour Index Direct Green 6),Calcomine Black EXN Conc. (Colour Index Direct Black 38), Niagara BlueNR (Colour Index Direct Blue 151) and Eric Fast Scarlet 4BA (ColourIndex Direct Red 24); such acid dyes as Anthraquinone Green GN (ColourIndex Acid Green 25), Sulfonine Brown 2R (Colour Index Acid Orange 51),Sulfonine Yellow 213 (Colour Index Acid Yellow 40), Xylene Milling Black2B (Colour Index Acid Black 26A), Xylene Milling Blue FF (Colour IndexAcid Blue 61), Xylene Fast Rubine 3GP PAT (Colour Index Acid Red 57),Calcocid Navy Blue R Conc. (Colour Index Acid Blue 120), Calcocid FastBlue BL (Colour Index Fast Blue 59), Calcocid Milling Red 3R (ColourIndex Acid Red -151), Alizarine Levelling Blue 2R (Colour Index AcidBlue 51), Amacid Azo Yellow G Extra (Colour Index Acid Yellow 63); suchmordant-acid dyes as Alizarine Light Green GS (Colour Index Acid Green25); such basic dyes as Brilliant Green Crystals (Colour Index Basic'Grecn 1) and Rhodamine B Extra S (Colour Index Vat Blue 35); such vatdyestuffs ar Midland Vat Blue R Powder (Colour Index Va-t Blue 35),Sulfanthrene Brown G Paste (Colour Index Vat Brown 5), Sulfanthrene Blue2B Dbl. paste (Colour Index Vat Blue 5), and Sultanthrene Red 3B paste(Colour Index Vat Violet 2); various soluble vat dyestuffs; such acetatedyes as CellitonrFast Brown 3RA Extra OF (Colour Index Dispersed Red13),

Artisil Direct Red 3BP and Celanthrene Red 3BN Conc.

W additament in'a substantially permanent manner, despite repeatedexposure and subjection to washing, laundering and dry cleaningtreatments. 7

Whatisclaimedis: 1. A graft copolymer comprising between about 20 and 80percent by weight of (a) a mixture of monomers consisting of (1) fromabout 10 to 90 mole percent of a vinyl pyridine monomer of the formula:V

a a I a. -i o 'or wherein-one of the symbols G represents a vinylradical and the remainder are independently selected from the groupconsisting of hydrogen and alkylradicals contain- 'ing from 1 to 3carbon atoms; and (2) from 90 to 10 mole percent of at least one alkenylgroup-containing organic sulfonic acid compound selected from the groupconsisting of those represented by the formulae:

all wherein X is selected from the group consisting of hydrogen,saturated aliphatic hydrocarbon radicals cont-aining from 1 to 4 carbonatoms and alkali metals; Y is selected from the group consisting ofhydrogen, chlorine and bromine; R is selected from the group consistingof methyl and ethyl; Z is selected from the group consisting of hydrogenand methyl; m is an integer from 0 to 2; n is an integer from 1 to 2; pis an integer from 0 to 1; and r is an integer from 1 to 4; and (b) fromto 20 percent by weight of an N-vinyl lactam polymer.

2. The graft copolymer of claim 1 containing about equal proportions ofsaid mixture of monomers graft copolymerized with said vinyl lactampolymer.

3. The graft copolymer of claim 1, wherein said mixture of monomersconsists of (1) from about 30 to 70 mole percent of said vinyl pyridinemonomer of Formula I and (2) from about 70 to 30 mole percent of atleast one of said organic sulfonic acid compound selected from the groupconsisting of those represented by the Formulae II, III, IV, V and VI.

4. The graft copolymer of claim 1, wherein said vinyl lactam polymer ispoly-N-vinyl-Z-pyrrolidone.

5. Method for the preparation of a graft copolymer which comprisespolymerizing with from about 80 to 20 percent by weight, based on theweight of the resulting graft copolymer, of an N-vinyl lactam polymer,between about 20 and 80 percent by weight of a mixture of monomersconsisting of 1) from about 10 to mole percent of a vinyl pyridinemonomer of the formula:

Z (VI) taining 1 to'4 carbon atoms andal kali metals; Y is selected fromthe group consisting of hydrogen, :chlorine and bromine; R is selectedfrom -the group consisting of methyl and ethyl; Z is selected from thegroup consisting of hydrogen and methyl; m is an integer from to 2; n isan integer from 1 to 2; p is an integer from 0 to l; and r is an integerfrom 1 to 4.

6. Composition comprising a major proportion of at least about 80percent by weight, based on the weight of the composition, of (A) afiber forming polymer of an ethylenically unsaturated monomeric materialcontaining at least about 80 percent by weight of acrylonitrile and (B)a minor proportion of up to about 20 percent by weight, based on theweight of the compositicn, of a graft copolymer of (a) from about 20 to80 percent by weight, based on the weight of the graft copolymer, of amixture of monomers consisting of 1) from about 10 to 90 mole percent ofa vinyl pyridine monomer of the formula:

wherein one of the symbols G represents a vinyl radical and theremainder are independently selected from the group consisting ofhydrogen and alkyl radicals containing from 1 to 3 carbon atoms; and (2)from about 90 to 10 mole percent of at least one organic sulfonic acidcompound selected from the group consisting of those represented by theformulae:

all wherein X is selected from the group consisting of hydrogen,saturated aliphatic hydrocarbon radicals containing from 1 to 4 carbonatoms and alkali metals; Y is selected from the group consisting ofhydrogen, chlorine and bromine; R is selected from the group consistingof methyl and ethyl; Z is selected from the group consisting of hydrogenand methyl; m is an integer from 0 to 2; n is an integer from 1 to 2; pis an integer from 0 to to l; and r is an integer from 1 to 4; and (b)from 80 to 20 percent by weight of an N-vinyl lactam polmyer.

7. The composition of claim 6, containing between about 4 and 15 percentby weight of said graft copolymer, based on the weight of thecomposition.

8. The composition of claim 6, containing between about 5 and percent byweight of said graft copolymer, based on the Weight of the composition.

9. The composition of claim 6, wherein the content of either monomericconstituent in said mixture of monomers is between about 30 and 70 molepercent of the total of both monomeric constituents.

. 14 10. The composition of claim 6, whereincomponent (B) is a graft'copolymer of 2-vinyll pyridine and sodium styrene sulfonate withpoly-N-vinyl-2-pyrrolidone.

11'. The composition of claim '6, wherein component (B) is a graftcopolymer of 2-viny'lpyridine and vinyl 'benzyl sulfonate withpoly-N-vinyl2 pyrrolidone.

l2.' 1"he.composition of claim 6, wherein the 'acrylo- -nitrilepolymeris polyacrylonit'rile.

-IEL'The composition of claim 6 dispersed in a solvent forpolyacrylonitrile.

14. A filamentary shaped article comprised of a composition that is setfolth in claim 6.

15. Method for the preparation of a dye-receptive, antistatic, stable tolight and heat, synthetic, hydrophobic polymer composition whichcomprises immersing an aquagel of a fiber forming polymer of anethylenically unsaturated monomeric material containing at least aboutpercent by weight of acrylonitrile in the form of a shaped article intoa dispersion of a graft copolymer of (a) between about 20 and 80 percentby Weight, based on the weight of the graft copolymer, of a mixture ofmonomers consisting of (1) from about 10 to mole percent of a vinylpyridine monomer of the formula:

all wherein X is selected from the group consisting of hydrogen,saturated aliphatic hydrocarbon radicals containing from 1 .to 4 carbonatoms and alkali metals; Y is selected form the group consisting ofhydrogen, chlorine and bromine; R is selected from the group consistingof methyl and ethyl; Z is selected from the group consisting of hydrogenand methyl; m is an integer from 0 to 2; n is an integer from 1 to 2; pis an integer from 0 to 1; and ris an integer from 1 to 4; and (b) fromabout 80 to 20 percent by weight of an N-vinyl lactam polymer, untilbetween about 1 and 20 percent by Weight of said graft copolymer, basedon the weight of the resulting dry composition weight, is incorporatedin said aquagel; then drying said graft copolymer-containing aquagel toconvert it from the aquagel condition to a finished shaped anticle form.v 1

16. The method of claim 15, wherein said;v acrylonitrile polymer ispolyacrylonitrile.

(References on following page) References Cited in the file of thispatent UNITED STATES PATENTS MacGregor Mar. 11, 1947 Cameron et a1. Apr.8, 1947 Cresswell et a1. Oct. 21, 1952 Ham June 30, 1953 (Doover 'Feb.21, 1956 Coover etal. Ian. 1, 1957 16 Coover et a1. Jan. 1, 1957 CooverApr. 30, 1957 Glickfnan Jan. 28, 1958 Vandenberg June 3, 1958 Tousignantet a1 Nov. 18, 1958 FOREIGN PATENTS Great Britain Sept. 8, 1954 PatentNo, 3,036,033 May 22, 1962 Stanley A. Murdock et a1.

It is hereby certified that error a ent requiring correction and thatthe sa corrected below.

ppears in the above numbered patid Letters Patent should read as Column4, line 46, for "wall" read wool column 5, line 45, for "drop" read dopecolumn 12, lines 5 to 10, formula (II) should appear as shown belowinstead of as in the patent:

011 (cs -s0 x :olumn 13, lines 25 to 30, formula (I) should appear asshown )elow instead of as in the patent:

SEAL) .llest:

RNEST W. SWIDER nesting Officer DAVID L. LADD Commissioner of Patents

6. COMPOSITION COMPRISING A MAJOR PROPORTION OF AT LEAST ABOUT 80PERCENT BY WEIGHT, BASED ON THE WEIGHT OF THE COMPOSITION, OF (A) AFIBER FORMING POLYMER OF AN ETHYLENICALLY UNSATURATED MONOMERIC MATERIALCONTAINING AT LEAST ABOUT 80 PERCENT BY WEIGHT OF ACRYLONITRILE AND (B)A MINOR PROPORTION OF UP TO ABOUT 20 PERCENT BY WEIGHT, BASED ON THEWEIGHT OF THE COMPOSITION, OF A GRAFT COPOLYMER OF (A) FROM ABOUT 20 TO80 PERCENT BY WEIGHT, BASED ON THE WEIGHT OF THE GRAFT COPOLYMER, OF AMIXTURE OF MONOMER CONSISTING OF (1) FROM ABOUT 10 TO 90 MOLE PERCENT OFVINYL PYRIDINE MONOMER OF THE FORMULA;